Method of making soft unripened curd cheeses



United States Patent F p H p 3,232,768 METHOD OF MAKING SOFT UNRIPENED I a CURD CHEESES WilhelmineI-I. van Wieren, Syracuse, and Joseph C. Langherg, Peterhoro, N.'Y., assignors to The Borden Company, New York, ;N.Y., a corporation of New Jersey No Drawing. Filed-May 5, 1961, Ser. No. 107,913 -2 Claims. (Cl. 99-462) This invention relates to'soft, 'unripened curd cheese with improved keeping quality and to the method of making it, and has particular reference to the manufacture ofcrea'med cottage cheese.

Soft,unripened curd cheese, such as cottage cheese and crearnedcotta'gecheese, are very perishable and have a limited keeping quality due to their susceptibility to bacteriaLLyeasL-anKi mold spoilage. Creamed cottage cheese also is subject to'oxidative rancidity of the fat. At present, itisn'ce'ssary to employ rigorous sterilization procedures on theequipr'n'ent used tomake such cheese and also to'holdit attemperatures below 40 FJin order to preveritmicrobial spoilage and oxidative changes. Even so, the keeping quality and storage, life of the cheeses is limited.

It has now been found that such cheeses can be prepared which have greatly'improved ke'epingqualities and shelf lifejand which at the same time retain a uniform flavor.

Brieflystated, the present invention comprises washiri'g the softf'unripened curd cheese with an aqueous solution of a source of chlorine dioxide, followed by addition of a,,yeast and mold inhibitor to the washed curd.

The inventionalso comprises, in the case of creamed cottage'che'ese, high'he'at treatment of the cream mix and jadd itio n of an antioxidant thereto.

The invention futther comprises the resultant storage stable icheese.

Conventional.procedures are used in the manufacture ofthe soft, unripened curd cheese up to the time the curd is' washed. T hus, either an acid curd, made without rennet, or a rennet-curd, combined action of starter cul- 'ture and rennet, cottage "cheese can be made using either the shortsettingflor-long-setting. procedures. The curd isth'n icut, heated,- and the whey removed therefrom. In*cohventional procedures'the curd is washed after removal of the whey., This is done in order to firm and harderi' the curd to the touch 'and also to remove any whey thatfmay r'e'niain in the curd since the Whey would adversely hifect the-flavor of the cottage cheese. Ordinarily several washings with water are carried out with the curd being soaked in the Wash water for a period of time, usually -20 minutes, and then drained free of the water. Two to three washings are ordinarily used With the last washing usually containing'water at a cooler temperature, 40? or lower.

-In"accordance with .the present invention a source. of Tchlorinedioxide is .addedwto the wash water and a yeast and mold inhibitor to the washed curds to prevent the growth of any cont aminating"organismsand the further growth of the organisms in the starter culture. The conventional soakingt'ime of the curd in the wash water is not altered. The result is a marked increase in the keeping quality of the cottage cheeses.

The use of a source of chlorine dioxide in the wash water without the subsequent addition of the yeast and mold inhibitor to the curds does not give satisfactory results. In like manner the use of only the yeast and mold inhibitor is also unsatisfactory. It is necessary that both be used to obtain the increased keeping quality and uniform flavor.

The source of chlorine dioxide is added preferably to all of the wash Waters, although, if desired, and several curd.

3,232,768 Patented Feb. 1, 1966 wash waters are to be used, the first wash Water only need contain a source of chlorine dioxide. Addition of the source of chlorine dioxide to the first washwater appears to be more effective than addition to subsequent Wash water because of the higher temperature and lower pH.

After the last wash water has been drained from the curd the yeast and mold inhibitor is added to the curds. In preparing creamed cottage cheese the inhibitor is preferably added tothe creammix to be admixed with the curds.

The curd may then be salted, or left unsalted, and packaged for use; In some instances the curd maybe refrigerated prior to packaging. i

It has also been found-that the storage stability of the creamed cottage cheese can be greatly improved if the cream mix is heated to a temperature ranging from F. for 30 minutes to 300 F. for 1 second, ordinarily 180 F. for 20 minutes, prior to admixing with the cheese It is preferred to add a food antioxidant to the cream mix inaddition a to the heat treatment, in order to obtain the prolonged keeping quality.

It is also desirable to pack the creamed cottage cheese in such manner that oxygen is excluded. Thiscan Q b'e doneeither by the use of gas packing in-an atmosphere of nitrogen, or carbon-dioxide, vacuum'packingor by'filling the container with cheese so as to permit nolhead space.

Oxidative changes in the butter fat in the creaming mix are prevented or retarded bythe high heat treatment, with or without the addition of anwantioxidant,and/ or packing in the absence of oxygen.

As to materials, soft, unripened curd cheesemade by any conventional processmay be used. Also used is any conventional cream mixemployed to make creamed cot tage cheese. Examples of such cheeses and mixesare set forth in pages 382 to'404 of the Van Slyke and Price text Cheese, published-by Orange IuddPublishing-Gompany, Inc., of New York, New York (1952).

The chlorine. dioxide thatis used is anycommerically available source of chlorine dioxide, preferably a stabilized form, a water soluble chlorite,-suchas-sodium ehlor-ite, or other available source of chlorine dioxide that issafc for use in foods.

The-yeast and :rnold inhibitor used is selected from the group consisting of sorbic acid, potassium sorbate, sodium sorbate, sodium propionate, calcium propionate, sodium benzoate, calciumbenzoate, mixtures thereof, and other commercially available inhibitors commonly used in foods. Sorbic acid and potassium sorbate are the preferred inhibitors.

The antioxidant that can be used inthe'creammixin preparation of creamed cottage cheese includes nordihydroguaiaretic acid, propylgallate,butylated hydroxyanisole, ethyl :gallate, and commercially ava.ilable:food anti oxidants thatrare mixtures ofthe above listed. antioxidants and may have synergists added thereto. A specific lex ample is a propylene glycol solution of butylatedhydroxyanisole with propylgallate andcitric .acid.

Satisfactory proportions of the chlorine :dioxide are about 101,000 parts per million (p.p.m.) and normally 15-200 ppm. in the wash water. Higher proportions may be employed but they are economically unsuitable.

The proportion of yeast and mold inhibitor added to the curd corresponds, for 100 parts by Weight of the curd, to about 0.0l-0.1 part by weight and preferably 0.05-0.075 part by weight.

The amount of antioxidant added to the cream mix is about 0300 p.p.m., based on 100 parts by weight of the cream mix, and ordinarily about 10 50 p.p.m.

The treatment of the cottage cheese curds as outlined above prevents spoilage due to bacteria, yeasts and molds EXAMPLE 1 Cottage cheese curd, washed in the usual manner with three wash waters containing 7.5 p.p.m. C1 from sodium hypochlorite, was divided into two equal portions and creamed. The cream mix for both portions were identical with the exception that one of the cream mixes contained 0.075% sorbic acid. The cheeses were packed and stored at 47 50 F. and periodically tested for microbial growth. The results were as follows:

Table 1 Weeks N Addi- 0.075% Sorbic tions Acid (N 0 counts taken) 1 200, 000, 000 2 2, 600, 000 1 320,000,000 2 28, 000, 000

1 All slimy, mold on surface. 2 All slimy, no mold on surface.

EXAMPLE 2 Cottage cheese curd was made as in Example 1 and washed with three wash waters, each containing 7.5 p.p.m. C1 from hypochlorite. The curd was drained, divided in half and creamed, with one portion of the curd creamed with a mix containing 0.05% sorbic acid. The results were as follows:

Table 2 7.5 p.p.m. Clz From NaOCl No Sorbic Acid 0.050 Sorbic Acid 7, 400 6, 000 800, 000 700, 000 410, 000 720, 000 800, 000 (No count taken) 1 All samples covered with heavy black mold; large number of coliforms. 2 N0 mold detected after 5 weeks; no coliforms.

EXAMPLE 3 Table 3 p.p.m. C10 15 p.p.m. C104.-

Weeks No Sorbic 0.075% No Sorbic 0.075%

Acid Sorbic Acid Acid Sorb c Acid 1 N0 count possible; surface completely covered with mold. 2 Surface completely covered with mold.

Creamed cottage cheeses made by washing the curd with 200 p.p.m. chloride dioxide and adding 0.075% sorbic acid to the cream mix were found to be edible after 13 weeks with no slimy surface growth or mold contamination. There was a development of rancidity in the samples that had no antioxidant added or in which the cream had not been given high heat treatment The foregoing examples illustrate the unexpected superiority of th use of both a source of chlorine and a yeast and mold inhibitor over the use of either alone. Further, the prolonged storage life of the cheeses of the instant invention make it desirable to provide against oxidation of cream in the cream mix.

It will be understood that it is intended to cover all changes and modifications of the examples of the invention herein chosen for the purpose of illustration which do not constitut departures from the spirit and scope of the invention.

We claim:

l. The method of improving the keeping quality o creamed cottage cheese comprising washing the curds with an aqueous solution containing 10-1,000 p.p.m. of a source of chlorine dioxide, draining said curds, and mixing said curds with a creaming mix containing up to 300 p.p.m., based on 100 parts by weight of the creaming mix, of a food grade antioxidant, and ODS-0.075 part by weight of a yeast and mold inhibitor for every 100 parts by weight of the creamed curd.

2. The method of improving the keeping quality of creamed cottage cheese comprising Washing the curds with an aqueous solution containing l5200 p.p.m. of stabilized chlorine dioxide, draining said curds, and mixing said curds with a creaming mix containing 10-50 p.p.m., for every 100 parts by weight of the creaming mix, of a propylene glycol solution of butylated hydroxyanisole with propyl gallate and citric acid, and ODS-0.075 part by Weight, for every 100 parts by weight of the creamed curd, of sorbic acid.

References Cited by the Examiner UNITED STATES PATENTS 2,546,568 3/1951 Taylor 99-154 2,701,781 2/1955 Guevara 16-7-17 2,974,046 3/1961 Perry et a1. 99l62 A. LOUIS MONACELL, Primary Examiner. ABRAHAM H. WINKELSTEIN, Examiner. 

1. THE METHOD OF IMPROVING THE KEEPING QUALITY OF CREAMED COTTAGE CHEESE COMPRISING WASHING THE CURDS WITH AN AQUEOUS SOLUTION CONTAINING 10-1,000 P.P.M. OF A SOURCE OF CHLORINE DIOXIDE, DRAINING SAID CURDS, AND MIXING SAID CURDS WITH A CREAMING MIX CONTAINING UP TO 300 P.P.M., BASED ON 100 PARTS BY WEIGHT OF THE CREAMING MIX, OF A FOOD GRADE ANTIOXIDANT, AND 0.05-0.075 PART BY WEIGHT OF A YEAST AND MOLD INHIBITOR FOR EVERY 100 PARTS BY WEIGHT OF THE CREAMED CURD. 